MARTINEZ — The murder trial started Monday for a well-known former Contra Costa County football player accused of gunning down a Richmond man inside of a moving car.

Witnesses to the crime included the defendant’s own mother, who changed her story on the stand during a preliminary hearing. Also present for the killing was a man who defense attorneys say really murdered the victim and set out to blame the defendant.

Dixon resident Marshon Ardoin, 23, is charged with killing David Mallard, 28, of Richmond, in April 2016. Prosecutors say the motive had to do with revenge; Ardoin allegedly thought Mallard had something to do with the death of a relative who was killed in 2008. Mallard’s body was found miles away from the homicide scene, in an empty field in Bay Point.

The evidence includes statements Ardoin’s mother made to police implicating him. Another man also told police he was driving a van through Richmond an evening in April 2016 when Ardoin shot Mallard from the seat behind him. They then traveled to Bay Point where Mallard’s body was left in a remote area before the van travelled to Vallejo, where it was cleaned.

A gun linked to the shooting was later found at a Dixon apartment complex where police arrested Ardoin a month after the homicide. His DNA was recovered from the handle.

But Ardoin’s attorney, Anna Teruel, said the prosecution’s witness had a greater motive to kill Mallard, since he was closer to the woman who had been killed in 2008. Teruel also said there were five DNA profiles found on the gun, and that Ardoin’s DNA was found on the handle, not the trigger.

She said there was “no evidence” Ardoin and Mallard had any animosity between them.

With regards to the statements by Ardoin’s mother, Teruel said the woman was in fear of her life when she implicated her son to police. She said the day of the homicide, the real killer had held a gun to her head and threatened that if she didn’t implicate Ardoin, he would kill her.

She said Mallard’s body had been dragged out of the van by his arms and that the killer rifled through his pockets before leaving the area.

Among the prosecution witnesses to be called Monday morning was Mallard’s mother, who said she had last seen him getting into the van sometime after 4 p.m. the day he was killed. She said the last thing he told her was, “Mom, I’m gone,” as he left the house, but that she went out front to watch him go.

“The Good Lord had told me to watch and see who your son is leaving with,” she testified. She said she recognized the driver as Mallard’s lifelong friend, but didn’t recognize another person in the car, who she said was wearing a baseball cap.

Ardoin was a running back for El Cerrito High School and played for Contra Costa College in 2015.

Nate Gartrell covers crime, politics, and corruption in Contra Costa County. He joined the Bay Area News Group in 2014. Outside of journalism, he doesn't do much. He aspires to visit all 30 Major League Baseball stadiums. Reach him at 925-779-7174.

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